Phoma Blight of Fir and Douglas-Fir Seedlings in a California Nursery. J. T. Kliejunas, Plant Pathologist, USDA Forest Service, Forest Pest Management, San Francisco, CA 94111. J. R. Allison, Plant Pathologist, USDA Forest Service, Forest Pest Management, San Francisco, CA 94111; A. H. McCain, Extension Plant Pathologist, Department of Plant Pathology, University of California, Berkeley 94720; and R. S. Smith, Jr., Plant Pathologist, USDA Forest Service, Forest Pest Management, San Francisco, CA 94111. Plant Dis. 69:773-775. Accepted for publication 8 April 1985. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1985. DOI: 10.1094/PD-69-773.

Phoma eupyrena was consistently associated with needle cast and blight of red fir (Abies magnifica) and Douglas-fir (Pseudotsuga menziesii) seedlings at a nursery near the coast of northern California. Symptoms typically developed during the dormant period between the first and second growing season. Heavy rains and soil splash resulted in the buildup of soil cones around the stem and lower crown, followed by infection of lower needles or buds by the soilborne fungus. Inoculations of greenhouse-grown seedlings with P. eupyrena in soil resulted in symptoms identical to those observed in the field. Protective fungicides tested on red fir gave little or no control. The addition of a redwood mulch and the use of a shade cover reduced soil splash, soil cone formation, and disease incidence.